US1474484A

US1474484A - Machine for casting bushings

Info

Publication number: US1474484A
Application number: US457270A
Authority: US
Inventors: Larsson Thure
Original assignee: Norton Co
Current assignee: Saint Gobain Abrasives Inc
Priority date: 1921-03-31
Filing date: 1921-03-31
Publication date: 1923-11-20
Anticipated expiration: 1940-11-20

Description

Nov. 20, 1921;; 1,474,484

T. LARSSON MACHINE FOR CASTING BUSHINGS Filed March 31. 1921 5 Sheets-Sheet 1 77: are Lw'wm Nov. 20, 1923. 1,474,484

. T. LARSSON MACHINE FOR CASTING BUSHINGS Filed March 31, 1921 5 Sheets-Sheet 2 FLgIZ 9 10 E i m-j; l I I 1' 27 /7/ in 7 1 30 62 22 i?! l i ,e/ 1' 3 I s' o i: 27 k1, w 7 l 3 fk j: w u

Nov. 20 1923. 1,474,484

T. LARSSON MACHINE FOR CASTING BUSHINGS Nov. 20 1923. 1,474,484

T. LARSSON MACHINE FOR CASTING BUSHINGS Filed March 31 192] 5 Sheets-Sheet 4 lfi 0011101 Tmlm Lmassm 5y (W EMJN UWQQA,

Nov. 20 1923. 1,474,484

i LFHQSEHDN MACHINE FOR CASTING BUSHINGS Filed March 31. 1921 5 Sheets-Sheet 5 Mhesses. ,lmwzzior 77mm Jam's-012.

may

Patented Nov. 20, 1923.

v UNITED STATES PATENT- OFFICE.

TEUBE LABSBON, OI WORCESTER, MASSACfiUSETTS, ASSIGNOR TO YORTON COMPANY,

OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

MACHINE FOR CASTING BUSHINGS.

Application filed larch 81, 1921. Serial No. 467,270.

To all whom it may concern:

Be it known that I, THURE LARSSON, a citizen of the United States of America, residing at Worcester, in the county of Worcester and State of Massachusetts, have invented certain new and useful Improvements in Machines for Casting Bushin s, of which the following is a full, clear, an exact specification.

My invention relates to a casting machine and more particularly to a machine for casting bushin s, such as the lead bushings of abrasive w eels.

To insure a good fit between the central hole of the grinding wheel andthe s indle of the machine on which it is intende to be used, it is the practice to cast a lead bushing around the center hole of the wheel. The operation of casting this bushing has heretofore been done by hand. The wheel is placed over an arbor and suitably centered as by means of a chuck, so as to leave an annular space between the arbor and the periphery of the hole and the molten lead is then oured by hand into this annular space. his usually leaves irregular and rough masses of lead around the opening and projecting beyond the flat sides of the wheel, which necessitates trimming the bushing to make it even with the sides; Furthermore, it requires a number of manual operations for each bushing cast, such as clamping the wheel in the chuck and dipping the molten metal out of a pot by han an then pouring it into the annular space between the arbor and the periphery of the hole,

as well as placing the wheel in position over the arbor and removing it after the bushing is cast, the latter being, in some cases, a rather difficult operation when performed by hand because the wheel is liable to stick on the arbor due to the expansion of the arbor by the heat.

It is an object of my invention to'overcome these difiiculties and construct a machine which is simple in design. highly efficient in operation and by the use of which I am enabled to increase production with a minimum of manual labor and expense.

lt is a further object of my invention to construct .a machine which, when set in motion, requires only that the wheels to be hushed be supplied'to it and the bushed wheels removed therefrom by the operator, the o eratlons of holding and centering the whee and casting the bushing, being automatic.

It is a still further ob'ect of my invention to provide a machine 0 this type having a relatlvely movable arbor and wheel support to cause the arbor to roject into the center hole of the wheel to orm an annular s ace between the arbor and the periphery o the hole and to rovide automatic means for causmg this re ative movement and allow the molten lead to flow from the resergoir to said annular s ace.

It is a still urther object of my invention to provide eificient means for holding. the wheel and forming a mold therewith, while the lead is being poured into the wheel hole, Y

and permit none of the lead to escape from the temporary mold, thus rendering unnecessary the operation of trimming the bushing after casting.

It is another object of my invention to avoid the extra operation of manually stamping the wheel with various indicia to denote the grain and grade of the wheel by providing my machine with these indicia on a Barter parts ofthe mold formed while the ushing is being cast, whereby the proper markings are cast-into'the lead.

It is a still further object of my invention to provide cam means for operating the wheel-holding chuck and the mold-forming means, said cam means being timed to actuate the various devices in proper sequence.

It is a still further object of my invention to provide a simple means for disconnecting the automatic chuck operating mechanism to allow of the adjustmentof the chuck jaws by hand.

To these and other ends, the invention consists in certain improvements and combinations of parts, all as will, hereinafter be more fully described, the novel features being pointed out in the claims at the end of the s cification.

Re erence being had to the accompanying drawings in which like numerals indicate like parts:

Figure 1 is a central longitudinal vertical section taken substantially on the line 11 of Fig. 2, parts of the lead pot being broken away;

Fi 2 is a horizontal section taken substantiall on the line 2-2 of Fig. 1,, the weights eing omitted;

F g. 3 is a sectional plan taken substantially on the line 33 of Fig. 1;

Fig. 4 is a front view of the machine, parts being shown in section as indicated by the line 4--4 of Fig. 1, and arts'broken away;

Fig. 5 is a plan view o the wheel supportin and centering means; and

I ig. 6 is a section therethrough, these views'showing an arbor of smaller diameter and the wheel su porting and centering means otherwise a apted to hold a smaller wheel than that shown in Figs. 1 and 4;

Fig. 7 is a sectional detail showing the manner of mountin of a chuck jaw taken substantially on the ins 7-7 of Fig. 6;

Figs. 8 and 9 are elevational and sectional views respectively of the pedal-operated clutch mechanism for starting and stopping v sectional view and the machine.

Figs 10, 11 and 12 are detail views of the mechanism for disconnecting the means for automatically operating the chuck jaws,

these views being taken at right angles toplace in'timed relation by means of a set of cam mounted on a cam shaft 5 in the base each other;

Fig. 13 is a sectional plan on an enlarged scale of the mechanism for actuating the lead pot valve;

Fig. 14 is a side elevation thereof;

Fig. 15 is a front elevation thereof, parts being broken away;

Fig. 16 is a detail sectional view of the spout and valve and part of the valve operatin means;

Fig. 1 is a top- 1plan view, Fig. 18 a ig. 19 a bottom plan view with parts broken away of the bottom mold-formlng late, showing the manner in which the in icia are connected thereto; an

Fig. 20 is a cross section through the wheel and the mold-forming parts showing the or forming a bushin position of these parts when the lead is pouring.

In accordance with my invention I provide a machine for casting a metal bushing in an abrasive wheel which comprises a support 1 on which various sized abrasive wheels may be centered and clamped in osition, and an automatic mechanism of proper thickness in correct axial position relative to the wheel periphery. In order toform the bushing hole of a desired size I utilize acore 2 of suitable diameter and removably insert the core .into thewheel and pour molten metal around it. The wheel support cooperating with the core may form the bottom of the mold and the molten metal-may be poured through an opening in a top mold plate which i adapted to be adjustably positioned or clamped against the, upper surface of the wheel,

aevaaee brou ht against the upper face of the whee a definite amount of molten metal is caused to flow from a heated reservoir 4 into the mold, after which the core'is moved relative to the abrasive wheel to expel the surplus molten metal and. produce a finished surface on the bushing due to the sliding movement of the core relative to the bushing material. Thereafter relative movement between the wheel and mold top is caused to release the wheel and the core is returned to its initial position. These movements are all caused to take of the machine, the cam followers which are operatively connected with the movable mold top shaft 5 extends transversely of the base of v the machine 6 and is supported in suitable bearings 7 in the upright webs 8 integrally formed with the base. Rising from the base 6 is a substantially rectangular casing 9 preferably made in sections to facilitate the assemblin of the machine, this casing serving to'enc ose most of the movable part of the machine. One end of the shaft 5 projects through this casing and is formed with a squared portion to receive a wrench or other tool to enable the operator to turn the shaft to any position or to restore the parts to their normal position in case the machine should stop for some reason. The opposite end of this shaft is provided with a sprocket gear 10 connectedby a chain 11 to a power shaft 12 journalled nearthe top of the casing and driven by any suitable means, as bymeans of a belt 13 and pulley 1 1 driven from a countershaft (not shown). The

sprocket gear 10 is normally loose on the shaft 5 but is adapted to be connected therewith at the will of the operator by means of a suitable clutch mechanism, shown in detail in Figs. 8 and 9, controlled by a foot pedal 16. The cam shaft 5 is provided between its bearings with three separate cams '20, 21 and 22, all suitably splined to the shaft to rotatetherewith. i

The rotation of the cam 22,.which I shall hereinafter term the main slide operating cam, effects the 0 erations of forming the. complete mold. a lowing the lead to flow into the mold and forcin the surplus metal out of the mold to form the completed bushing and it eflects these operations through the following instrumentalities. It will be observed that the arbor or core 2 is shown in Fig. 1 formed at its lower end with a reduced extension fitting snuglywithin a sleeve-like member 26 rigidly connected to the base. In the drawings I have shown this sleeve-like member as made of a plurality of sections for constructional purposes. On opposite sides of this sleeve and referably formed integrally with the we 8 extending upward] from the base 6, I have shown the substantially vertically extending guides 27 (Figs. 2 and 3). 'These guides are T-shaped in cross section and serve to guide the vertically operable main slide 3 as well as the wheel support 1, which has a downwardly extending slide 29 connected thereto. The

slides

3 and 29 are provided with the usual gibs 30 (Figs. 2 and 3) to take up wear.

On opposite sides thereof the main slide 3 is provided with ears 32 (Figs. 3 and 4) formed with vertically arranged openings, through which extend the posts 33 with a wringing fit. The lower ends of theseosts are formed with flanges 34 which ear against the cars 32 and the posts extend upwardly through openings 35 in the casing 9, and are connected at their upper ends by the cross beam 36. The main slide 3 and connected parts are normally held in raised position by means of springs 37 surrounding guide pins 38 connected to the base 6 and extending upwardly in axial alignment with the posts 33. The posts 33 are hollow and adapted to telescopically receive the upper ends of the guide pins 38.

The cross beam 36 carries a part 41, which forms the top of the casting mold, preferably in the form of an annular plate, the cooperating part or plate 42 being movably mounted on the wheel support'l. These parts are provided with openings 43 of a size adapted to slidinglv fit the arbor 2 and are removably connected in any suitable manner to their respective parts to allow of the substitution of mold parts to fit different sized arbors and wheels. (Compare Fig. 1 with Figs. 5 and 6, the last two showing a work support adapted to receive smaller wheels than that shown in Fig. 1.) The cross beam is further provided with a conduit 44 opening at its lower end into the mold part 41 and connected at its upper end with a funnel-shaped member 45 adapted to catch the flow 0 lead from the reservoir 4, these arts serving asa channel or conduit for the ead to direct it to the mold.

The means for operativel connecting the causes vertically reciprocating movement of the main slide, the cam 22 positively lowering the slide in opposition to the s rings 37, which latter return it to its raise position.

The work support 1 is normally held in elevated position b any suitable means, such as a counterba ancing member 54, the weight of which is sufficient to hold the work support 1 with the work thereon so'that a shoulder 55 on the downwardly projecting slide 29 on the work support is in engagement with the top of the housing 9. but not suflicient to interpose any appreciable resistance to the downward movement of the work support. This approximatel balanced relation of the weight 54 and work support and work is desirable to avoid too great a pressure on the sides of a wheel on the support which might crack a thin wheel, especially if it should happen to be slightly warped. The weight is shown adjustably mounted on one arm of a lever 56 pivoted at 57 to a frame member depending from the top of the housing 9, the other arm of this lever being connected, as by a link 58, to the slide 29 forming part of the work support. The weight is held in adjusted position by a set screw 59 and access thereto can readily be had by removing the end closure 62 (Fig. 1) of the housing 9, which is held in lace by screws.

To furt er guard against the possible breakage of a thin wheel due to the pressure of the mold part 41 on its upper side during the normal operation of the machine, I preferably mount the lower mold part 42 to allow slight relative sliding movement between it and the work support 1. The part 42 snugly fits the arbor 2 and s mounted at the upper end of a sleeve 63, preferably on a flanged bushing 61, this bushing being removable to allow the substitution of difierent sizes to fit different sized arbors. (See Figs. 1 and 6.) The sleeve 63 slides within From this construction it will be apparent that the rotation ofthe cam shaft.

the reduced cylindrical part 64 of the slide I 29. The sleeve 63 is formed with an external annular shoulder 69 (Fig. 4) which strikes an upwardly projecting shoulder on the part 64 which limits its u ward movement, and it is held in raise shown in Fig. 1, by a counterweight 65 connected to it in a manner similar to the conpositlon, as

I 5, 6 and 7, and having three radially sliding 9 equal expansion of the arbor and bushing due to unequal heating, (the arbor being, during the casting operation, in direct contact with the molten lead) that thesleeve will not return'to its raised position under the influence of the weight 65. I have provided for such a contingency by mounting a cam roller 68'on that arm of the lever 66 whichis connected to the sleeve 63. This roller is adapted to be engaged by t-hecam 21 on the cam shaft 5 immediately after the cam 22 allows the springs 37 to return the main slide to its raised position, the cam 21 acting to return the sleeve to its raised po-' sition, as shown in Fig. 1.

I preferably form the work support 1 as a universal chuck, shown in deta1l in Figs.

members or jaws located substantiall 120 apart and formed with grooves 71 s1;

ing in guide ways 72 (Fig. 7) the latter formed in the to plates 74. These top plates are referab y fastened to the body of the work holder or chuck 1 by means of screws 75 (Figs. 5 and 6). The radiall sliding members have downwardly exten ing portions forming nuts 76 engaging radially extending screws 77' mounted for rotation but held against endwise movement in the body of the chuck. One or more of these screws may extend some distance. outside the chuck body and be formed with a squared or otherwise shaped portion 78 (Fig. 6) adapted to receive a wrench for turning them to move the sliding members radially. The screws areall geared together. as is the practice in this class of chuck, by having bevel gears 81 thereon meshing with. an annular gear 82 mounted for rotation within the chuck body.

I have provided means for automatically moving the chuck jaws to operative and inoperative positions, and I e set these movements in timed relation with the other operations performed by my machlne, by means of the cam- 20 on the cam shaft 5 and a spring 83, and connections between the cam and the chuck. These connections may comprise aspur pinion 84 (Fig. 6) mount" ed on a stud 85 extendin through the chuck body, this pinion mes. ing with internal spur teeth on the annular gear 82. The stud 85 is connected with a shaft 86 extending down into the housing 9 and formed with telescoping sections 87 and 88 (Figs. 10, 11 and 12), thelatter section being supported in

bearings

91, 92 and 93, and conestates nected adjacent itslower' bearing 93 with a spiral pinion 94. This pinion meshes with a spiral-toothed sector 95 mounted to rock on the shaft 46 and urged upwardly (Fig. 1) to move the chuck jaws into en agement with the periphery of the whee? by the spring 83. side of the sector 95 in the path of the cam 20, which operates at predetermined times to rock the sector downwardly in opposition to the spring 83 to open the chuck aws.

In order to accommodate the c uck for wheels of different diameters, I may mount the adjustable work-engaging arts on the slidin members or aws 0, such adjustment eing made possible by providing a pin and slot connection 101 between said A roller 97 is mounted .on the parts and jaws, said parts being clamped in position by means of the nuts 102. This-adjustment 1s a relatively slow process and I may further provide means for effecting a more rapid adjustment of the jaws 70 wlthin predetermined limits to accommodate them for wheels of difierent diameters.

This is conveniently accomplished by the formed with two flanges forming an annular groove 105 therebetween. Ayoke 106 engages in this roove and is connected to a shaft 107 exten ing outside the housin 9 andformed with a handle 108. 'Now, i it is desired to adjust the chuck jaws, the operator merel raises the handle 108, which disengage's tli e

clutch teeth

103 and 104 and allows him to move the jaws 70 by turning one of the screws 77. Upon release of the handle, the

clutch teeth

103 and 104 will antomatcally interlock under the influence of gravity. f .they do not inter-mesh at once, a slight turning movement of the screws 77 will allow them to do so.

In order to allow the lead to flow from the reservoir 4 by gravity, I have shown it mounted at some distance above the. work support and easing 9, being supported in that position by means of the standards 109 and a plate 110 connecting the upper ends of the standards. The reservoir may be provided with an suitable means for bringing the lead to t e proper temperature and maintaining it at such temperature. I have shown it Wrapped with a hlgh resistance coil 111 through which a current of suitable strength is assed from a source of energy (not shown) connected to the coil by the

wires

112, 113. The coil and reservoir are covered with a suitable insulating material shown at 114. I may provide means, controlled by a thermostat 1K5, for making and breaking the current through the heating coil 111. This means may comprise a solenoid operated switch 119 in the heating coil circuit. When the solenoid 116 is energized the switch is closed, but when it it de-energized the switch is opened, as by avity. The thermostat controls the openin and closing of the circuit through the solenoid. as will be apparent from an inspection of Fig. 1.

To permit the lead to be drawn from the reservoir at the proper time and in the desired direction, I provide it with a spout 117 adapted, during the operation of the machine, to cooperate with the funnel-shaped member 45 on the cross beam. The flow of lead from the spout is controlled by a valve mechanism 120 shown in detail in Figs. 13, 14, 15 and 16, actuated by the movement of the main slide 3 and its connected cross beam 36. I have shown this valve mechanism as comprising a sliding valve member 121 normally held on its seat 122 as by a spring 123. through the medium of a rock shaft 124 and a crank arm 125 on said shaft. The end of this arm 125 is enlarged and rounded and engages'a hole 126 in the sliding valve member 121, as is clearly shown in Fig. 16. It is desirable for the most efficient working of my machine under various conditions of operation that the valve be opened 'and closed almost instantly so that the time of flow of the lead may be controlled to a nicety.

In my preferred form, the means for opening and closing the valve comprises a trigger mechanism 127 connected by an an led bracket 128 to a depending flange 118 W ich may be integral with the plate 110 supporting the lead reservoir. This mechanism is operated by cam surfaces 129 and 130 (Fig. 15) on a standard 131 connected to the cross beam 36 and comprises a sleeve 132 mounted for longitudinal sliding motion on a rock shaft 133 but held against relative rotation thereon by means of the keyed connection 134 (Fig. 13). This sleeve is normally held in raised position against the tension of a coiled spring 135 surrounding the shaft 133 and compressed between a fixed collar 136 on the shaft and the upper end of the sleeve. The means for holding it in this position comprise a lug 137 thereon engaging the upper surface of a projection 138 on the bearing sleeve 139 of the bracket 128 in which the shaft 133 is journaled and held at one limit of its rocking movement with the lug 137 abutting against a stop 140 on the bearing sleeve 139 by a spring 141. The

sleeve 132 is further provided with a laterally extending projection 142. which normally lies directly over one arm 143 of a bell crank lever ri idly connected to the rock shaft 124, the other arm 144 of the lever being connected to the spring 123. A laterally extending arm 147 attached adjacent the lower end of the rock shaft 133 cooperates with the cam surfaces 129 and 130 onthe standard 131 to control the o eration of the valve at the proper time. he cam surface 129 is preferably carried on-a vertically movable slide 148 which is connected as by screws 149 to a nut 150, the connecting parts of the nut and slide extending through V operative to close it, the time during'which the lead is flowing can be readily controlled to adapt the machine to wheels of different thicknesses.

In the operation of theldevices-just de-v scribed, the main slide '3 and connected cross beam 36 descend until the cam surface 129 engages the arm 147, and rotates the rock shaft 133 and sleeve 132'until the lug 137 thereon slides off the projection 138 and the sleeve is shot downwardly under the action of spring 135, which is stronger than the spring 123,thus sliding the valve member 121 to open position. The rotary and downward movements of the sleeve will bring the end of the arm 143 of the bell crank lever close to the edge of the projection 142 so that a slight additional rotary movement of the sleeve in the same direction will bring these parts out of engagement and allow the valve member to return to its closed position under the action of its spring 123. This slight'additionalrotation of the rock shaft and sleeve is brou ht about when the arm 147' is engaged by t e cam surface 130, which extends laterally ashort distance beyond the cam surface 129, as is clearly shown in Fig. 15. After the arm 147 has moved up the cam surface 129, it will move along the straight vertical surface 148, during which time the valve is held open. On the return stroke of the main slide 3, the arm 151, rigidly connected as by screws to the standard 131. will, as the parts approach their upper position, engage the under side of the lug 137 and raise the sleeve 132 against the action of the'spring 135, until the lug 137 is raised above the projection 138, when the shaft and sleeve will be rotated to their initial position under the action of the spring 141. The engaging parts of arm 151 and lug 137 are preferably beveled to diminish the force required to. rotate the shaft to its initial positlon. Since the valve is in no case opened before the funnel-shaped member 45 is below the s out 117 on the lead 0t, when the main sli e 3 and the attache parts are in their lowest position, the member 45 will be some distance below the spout so that there may be more or less spattering-of the. lead when it strikes the member 45. vent injury to the operator or interference with the smooth operation of the machine because of this possible spattering, I provide the guard 154 extending above the funnel-shaped member 45 on all sides exce t the side facing the lead pot spout 117 an connected to the funnel in any suitable manner as b screws.

T e clutch mechanism for connecting the sprocket gear 10 to the shaft and the means for o erating it are shown in detail in Figs. 8 an 9. The sprocket gear is there shown rovided with a wear-resisting bushing 155 astened inside its hub 156 and is loosely mounted on a sleeve 157 keyed to the shaft 5. The gear is held in place on the shaft by a coller 158. The sleeve 157 is formed at its inner end with an annular flange 159 and across that face of this flange which is toward the gear are formed two aligned guiding rooves 160 arranged'on opposite sides of t e shaft, in which the lugs 161 on a radially movable clutch member 162 are adapted to slide. This clutch member is located between'the flange 159 and the hub 156 and is formed with a laterally extending clutch finger 163 adapted to engage with a notch 164 formed in an annular flange 165 on the hub of the sprocket. A spring 166 constantly urges the clutch member in a direction to cause its fingers to engage the notch and thus lock the sprocket gear to the shaft. To hold the clutch member in its inoperative position against the tension of the spring, I provide a weighted lever 168 connected to the clutch member by a link 169 and a bell crank lever 170. The lever 168 is '45" pivoted at 167 and is provided with an adjustable weight 171 at one end and connected to the link 169 at its opposite end. The weight tends at all times to urge the free arm of the bell crank lever 145 into engagement with the clutch member 162. When the shaft 5 is rotating the clutch member is rotated with it, and when the clutch member comes around to the position shown in Fig. 8, the projection 172 on the bell crank bears on a projection or knob 173 on the clutch member and forces it radially against the action of the spring 166 to release the clutch finger 163 from the notch 164. The shaft 5 is normally rotated at a comparatively slow speed, so that it will come to a stop almost instantly after the clutch is disengaged. -The parts will then remain in the position shown in Fig. 8, until the operator depresses the pedal 16 which is splined to the pivot'167 connected to turn with the lever and the .weight 171, thereby To preor wheels on which the sides are not per-.

fectly true, it is desirable to make some rovision to prevent the molten lead from owing through the irregular channels thus formed between the wheel sides and the swinging the free end of the bell crank into annular mold-forming

plates

41 and 42. I-

diameter slightl larger than the diameter of the wheel ho e, and bears with its inner periphery against a shoulder 176, the outer periphery being chamfered at 177 and held in place by the chamfered edge of a metal rizng 178 secured to the mold part by screws 1 9.

It is customary in the art of manufacturing abrasive wheels to manually stamp various indicia on the wheel bushing to indicate, for example, its grain and grade, after the wheel is bushed and trimmed, and I propose, since my machine is designed to bush the wheels in such manner as to avoid trimming the bushing afterwards, to provide means on my .machine for automatically casting these indicia in the bushing. In Figs. 17 to 19 I have shown one means for carryin this provision into eflect, the indicia or mar ings 180 being formed on the ends of pins 181 adapted to fit into a circularly screws 184. To insure the roper positioning of the indicia so that t e letters or figures, or whatever characters are used, may" be read in the -same direction, I may provide any suitable means for preventing the pins from rotating when in position and for preventing them from being assembled in the late 42 in any other than the desired anguar'relation. .Ihave shown the pins formedwith elongated. heads 185 located eccentric lar relation.

sleeve 63 carrying the lower mold to' the axis of the pins, these pins fitting within correspondingly shaped recesses 18 6 on the plate 183. It will be seen from this .construction that the indicia are readily interchangeable and formed to allow others to be substituted as desired, and that they can beoassembled only in their proper angu In describing the operation of my machine, let us assume that the lead 1n the reservoir 4 has been brought to the proper temperature and the parts of the mach ne are in the position shown in Figs. 1 to 4. The foot pedal is in the depressed position and the cam shaft 5 is accordingly connected to the power shaft through the clutch mechanism described above. The cam shaft is rotating in the direction indicated by the arrow (Fig. 1), a wheel W is in position on the work support or chuck 1, the chuck jaws action of the spring 83, and the mainslide 3 with the connected cross beam 36 is descending under the action of the cam 22. The roller 97 on the spiral sector has just dropped from the high point of its actuating cam 20 and the .roller 49 is riding up the cam 22. The work support 1 and t2;

art

are held in their raised position y the

v counterweights

54 and 65 res ctively. As

the cam shaft continues rotating, the main slide will continue to descend until the roller 49 reaches the point a (,Fig. 1) on the cam 22. Prior to reachin this point the mold part 41 engages the side of the wheel W to form with the inner periphery of the wheel hole, the lower mold part 42, and arbor 2, the complete mold for receiving the molten lead. The exact location of the roller on the cam 22 when this engagement takes place is, of course, determined by the thickness of the wheel. After this engagement the slide continues to descend until the roller reaches the point a on the cam 22, the wheel support orv chuck 1 and the mold art carrying sleeve 63 now moving with t e slide and causing the upper end of the arbor 2 to rotrude to some extent into the wheel ho e. The valve opening cam 129 on the valve operating mechanism acts to open the valve soon after this engagement, the time of opening depending of course on the position of the opening cam 129 on the standard 131. Before the valve is opened the funnel-shaped member will have descended below the spout on the reservoir, so that the molten lead flowing from the spout by gravity will be caught by this member and directed through the conduit 44 to the mold, as will be clear by an inspection of Fig. 20.

While the roller is travelling from the oint a to point I) on the cam, the main slide is held stationary because this portion of the cam forms a cylindrical surface, and this gives more time for the lead to flow. To stop the flow of the lead and to remove the surplus lead from the mold with the further rotation of the cam shaft, the roller again rides up. a short incline from the point 12 to the point a on the cam, which depresses the main slide until the top of the arbor 2 is on a level with the inclined drainage chute 187, from which the surplus metal flows to a pan 188 in position toreceive it;

While I have shown and described the cam 22 shaped to give a pause to the downward movement of the slide while the lead is pouring, such a construction may, under certain conditions of operation, be dispensed with because the timing of the flow of the lead can be regulated by adjusting the cam 129 of the valve operating mechanism. In-

stead of having the cylindrical portion from point a to point I) on the cam and a relatively ing from a to 0. In any case it is desirable to have a relatively rapid descent of the slide 3 until the mold part 41 engages the wheel and thereafter a somewhat more gradual descent until the lead is poured. The flow of lead is stopped by the automatic closing of the valve during this last downward movement of the main slide bv the instrumentalities above described. The time involved during which the lead flows is definitely determined by the shape of the cam and the speed of movement ofthe arts which'operate the valve, these being a justable and controllable by the operator.

The main slide is held stationary in its lowest position while the cam shaft rotates through approximately 120, or aslong as maybe desired to give the lead time .to cool and set. During this time the roller moves over a cylindrical portion of the'cam from -0 to d. Frgm the point (i the roller rides down a sharp incline on the cam 22 and the main slide is allowed to rise under the action of the springs 37 to its raised position. removing the upper mold portion away from the wheel, and allowing the work support and sleeve 63 to rise under the action of the

weights

54 and 65 respectively. If the frictional resistance between the arbor 2 and the sleeve 63 should, for any reason, be greater than the lifting force exerted by the weight 65, the sleeve 63 \vill, nevertheless, be returned to its raised position because of the engagement of the cam 21 with the roller 68 on the lever 66. During the latter part fining the center hole of the wheel and the main slide again starts to move downwardly for a succeeding operation. During the time the chuck jaws are held open the operator removes the finished wheel and replaces it by an unfinished wheel. The valve operatin trigger mechanism is also reset durin the final stages of the upward movement 0 the slide.

Having thus described my invention,.1t will be evident that changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope thereof as set forth in the claims, and I do not wish tobe otherwise limited to the details herein disclosed, but what I claim and desire to secure by Letters Patent is:

1. A machine for casting a metal bushing in an abrasive wheel comprising a support for the wheel, means to center wheels of various sizes thereon, means including a movable core which cooperate with the wall defining the hole in said article to form a mold, and means for automaticall molten metal to flow into said mo d.

2. A machine for casting the lead bushings of abrasive wheels comprising a wheel support, a movable core, a movable m'old top having a passage therethrough for molten metal, means for automatically positioning the mold top and core relative to said wheel and support whereby said support, mold top, core and the wall defining said hole form a mold, and means for automaticall causing molten lead to flow into said mol 3. A machine for casting the lead bushings of abrasive wheels comprising a wheel support, means cooperating with the wall desupport to form a mold, means for automatically causing molten metal to flow for a definite time interval into said mold, and

means to expel any surplus lead and form the completed bushing.

4. A machine for casting metal bushings in wheels comprising a wheel support, a reservoir for molten metal, means for heating the same, means for automatically feeding a predetermined amount of molten metal from said reservoir into the wheel hole, and means including a core insertable into said hole to form a finished bushing. of said molten metal,

5. A machine for casting the lead bushings of abrasive wheels comprising a wheel support a core member, means cooperating with said wheel support, core member and the wall defining the center hole of the wheel to form a mold, a reservoir for molten lead, mean to-heat said lead in the reservoir, and means to cause the molten lead to flow from said reservoir into the mold in timed'relation with the mold forming means.

6. A machine for casting the lead bushings of abrasive wheels comprising a wheel causing support, means to' center a wheel thereon, a core member insertable into the wheel hole, means cooperating with said wheel support, core member and the wall defining the center hole of the wheel to form a mold, a reservoir for molten lead, means for causing a definite amount of molten lead to flow from said reservoir into the mold, and means for relatively moving said core member and the other mold parts to expel any surplus lead and form the completed bushing.

7. A machine for casting the lead bushings of abrasive wheels comprising a relativel -,movable wheel support and core mem er, means including a mold part for moving said support and member relatively to a redetermmed extent to cause the core mem en, to projectfinto the center hole of the wheel, and mechanism to permit the metal to flow into the mold formed by said wheel support, mold part, the wall definin said wheelhole and core member, sai means thereafter being adapted to cause further relative movement between the core member and wheel support to expel. the surplus lead to form the completed bushing.

8. A machine for casting the lead bushings of abrasive wheels comprising a relatively movable work support and core, means including a mold part for moving said support and core relatively to form a mold therewith and with the wall defining the hole in the wheel on the su port, mechanism actuated after said re ati-ve movement to permit lead to flow into said mold,

9. A machine for casting metal bush-- ings in a wheel comprising a wheel support,-

movable members thereon .for clamping against the wheel periphery to center it, means for moving said members, a core, means for positioning the core relative to said wheel and support, whereb the support, the core and the wall de ning said hole form a mold, a reservoir for molten metal, means for heating the same, means for automatically causing molten metal to flow from said reservoir into the mold, and means to expel surplus metal from the mold and form t e completed bushing.

10. A machine for casting the lead bushings of abrasive wheels comprising a wheel support having movable members for clamping against the wheel periphery to center it and hold it in place during the pouring operation, means for moving said members, a relatively movable core, means including a mold part for causing relative movement between the wheel support and core to form a mold with the wall defining members and the core to expel surplus metal the center hole of the wheel, a reservoir for molten lead, said last-named means allowing the metal to flow from the reservoir to the mold, and mechanism for operating said moving means in properly timed relation.

11. A wheel bushing machine comprising relatively fixed and movable annular moldforming members, a core normally project-- ing through the opening in one of said members, means for moving said members relatively into engagement with the sides of a wheel to form a mold with the wall defining the center hole of the wheel, a reservoir for molten metal, and means operable subsequently to said mold-forming movement to allow the metal to flow from the reservoir into said mold, and means for moving said core and members relatively after the mold has been filled to expel the surplus metal and form the completed bushin s.

12. machine 'for casting metal bushings in wheels comprising a core, moldforming members movable relative to each other and said core adapted to project through one of said members, a reservoir for molten metal, automatic means for moving said members relatively to each other to engage the opposite sides of a wheel and form a mold with said core and the wall defining the center hole of the Wheel, and an automatically actuated device to cause the molten metal to flow from said reservoir into said mold, said means finally causin further relative movement between said and form the completed bushing.

13. A wheel bushing machine comprising a relatively fixed vertically arranged core, a wheel supporting means slidably mounted on said core, a main actuating slide mounted to slide in a vertical path, a reservoir for molten metal, a valve for controlling the flow of metal from said reservoir, opposed moldforming memberson said wheel support and main actuating slide respectively, means for moving said main actuating slide to bring the mold-forming member thereon in contact with the side of the wheel to form the' comprising opposed mold-forming members for engagement with the sides of a wheel to be treated, said members being yieldingly held against the wheel to allow for variations in the thickness of wheel, a core normally adapted to extend through one of said members, means for first moving said members in engagement with .the wheel and thereafter moving said members and wheel bodily relative to the core to cause the latter to extend into the wheel hole, a reservoir for molten metal, a'valve mechanism opere ated by said means to permit metal to flow from said reservoir into the mold formed by said mold-forming members, core and the periphery of the wheel hole.

15. In a machine for casting bushings, the combinat'on of a work sup ort, means for clamping the work in os1t1on on the support comprising mova le jaws, automatic means for moving said jaws to open and closed positions at each operatiomand means for disconnecting the automatic means to 7 allow of manual adjustment of the jaws for different sized work.

16. In a machine for casting the lead bushings of grinding wheels, the combination of a work support, means for clamping the work in position on the support comprising movable jaws, yielding means for automatically clos ng said jaws, positive means for automatically opening said jaws against the action of said yielding means, means for disconnecting the automatic means including a manually operable clutch, and means for manually adjusting the jaws whileso disconnected from the automatic means.

17. A machine for casting the metal bushings of wheels comprising a wheel support, means cooperating with walls defining the center hole of the wheel and said support to form a mold, a device for automatically permitting molten metal to flow into'said mold, and mechanism for varying the time of flow of the metal, said means comp-risin plus metal 18. A machine for casting a metal bushing v (r a core adapted to expel any surto form the completed bushing.

within a, wheel comprising a wheel support, .a

reservoir for molten metal, means to heat the same, means for automatically causing molten metal to flow from said reservoir into the hole of the wheel, means for varyingthe time of flow of said metal, a core, and means for causing relative movement between the core and Wheel support to insert the core within said hole and form a finished bushing of the' molten metal.

19. A machine for casting metal bushings in wheelscomprisinga wheel support, a core movable means cooperatingwith the wall defining the center hole of the wheel, the support and core to form a mold, a reservoir for 'molten metal, and means for automatically controlling the flow of metalfromsaid reservoir to said mold comprising a valve mechanism and devices on said movable means for operating said valve mechanism at predetermined. points in the movement of said movable means. i

iln@

20. A machine for castinr metal bushings I in Wheels comprisin a wheel support, means cooperating with said support and with the wall defining the center hole of the wheel to form a mold, a reservoir for molten metal, a valve for permitting the molten metal to flow from said reservoir-into the mold, said means including a'movable member, mechanism operable by said movable member tin yielding movement of said support paralle with the axis of the wheel, a core adapted to be located within the hole of the wheel, said support, core and inner periphery of the wheel being adapted to form a mold, means for automatically pouring molten metal Within said mold, and means for automatically moving the wheel support. a gainst said-yieldin pressure to move the wheel relative to t 1e core and form a bushing of said molten metal.

22. A machine for casting metal bushings in wheels comprising a wheel support, a reservoir for molten metal, means including a thermostat for heating and maintaining the metal at a substantially constant temperature, means for automatically causing a definite amount of molten metal to flow from said reservoir into the Wheel hole, and

means including a movable core to expel the surplus metal and form a finished bushing.

23. A machine for casting. metal bushings in wheels comprising mold forming members relatively movable into engagement with opposite sides of the wheel, one carr ing indicia in relief, a core cooperating therewith and with the walls of the wheel hole to forma mold, means for automaticall causing molten metal to flow into said mold: and means including said core to expel the surplus metal and form a bushing marked with said indieia.

24:. A machine for casting a metal bushing in an abrasive wheel comprising a. support for said wheel and a mold top which are relatively movable to engage the opposite sides of the wheel, said support and top ha ving openings therethrough in alignment with the wheel opening, a core movable into said wheel opening, means for maintaining a supply of molten metal, automatic: mecha nisms working in timed relation to cause the mold top to engage the wheel and a definite supply of molten metal to flow through said top into the mold defined by the support, mold top, core and internal wall of the wheel, then to move the core and wheel relatively to expel the surplus metal from the. mold and produce a finished bushing for the wheel. and thereafter to remove the mold parts from the wheel.

Signed at Worcester, Massachusetts, this 30th day of March 1921.

THURE LARSSON.